Accostando a due specchi ortogonali un tetraedro le cui facce sono due triangoli equilate...
A regular octahedron. Image taken from Giovanni Strüver's memoir Studi sulla Mineralogia ...
A regular octahedron. Image taken from Giovanni Strüver's memoir "Studi sulla Mineralogia...
The green straw, laid between the mirrors that form an angle of 90°, shows the 6 rotation...
The green straw, laid between the mirrors that form an angle of 90°, shows the 6 rotation...
The red straw, laid between the mirrors that form an angle of 45°, shows the 3 rotation a...
The yellow straw, laid between the two mirrors that form an angle of 60°, shows the 4 rot...
This drawing, attributed to Leonardo da Vinci and taken from the plates of Luca Pacioli's ...
This drawing, attributed to Leonardo da Vinci and taken from the plates of Luca Pacioli's ...
One of the five regular polyhedra, the octahedron, reconstructed, in two colours, in the k...
